N&#39;-alkyl and n&#39;-aryl-n-fluorenyl-p-phenylenediamines

ABSTRACT

1. N-FLUOROENYL-N&#39;&#39;-SUBSTITUTED PARAPHENYLENEDIAMINE IN WHICH THE N&#39;&#39;-SUBSTITUENT IS SELECTED FROM THE GROUP CONSISTING OF PHENYL, NAPHTHYL, TOLYL, XYLYL, AND ALKYL CONTAINNING 1 TO 20 CARBON ATOMS AND ALKYL CONTAINING 1 TO 20 CARBON TOMS WHICH IS SUBSTITUTED BY A SUBSTITUENT SELECTED FROM THE GROUP CONSISTING OF HYDROXY AND ALKOXY IN WHICH THE ALKOXY GROUP CONTANS 1 TO 4 CARBON ATOMS.

United States Patent Oflice 3,839,451 N'-ALKYL AND N-ARYL-N-FLUORENYL-p- PHENYLENEDIAMINES Jerry Donald Hunt, Cuyahoga Falls, Ohio, assignor to The Firestone Tire 8: Rubber Company, Akron, Ohio N Drawing. Original application May 22, 1969, Ser. No.

827,059, now Patent No. 3,625,913. Divided and this application Mar. 25, 1971, Ser. No. 128,121

Int. Cl. C07c 87/154 US. Cl. 260-576 3 Claims ABSTRACT OF THE DISCLOSURE N-fluoreny1-N-alkyl and aryl-p-phenylenediamines are new compounds. They are antiozonants in natural and synthetic diene rubbers.

This application is a division of my application Ser. No. 827,059, filed May 22, 1969 now 3,625,913.

N-fluorenyl-N'-alkyl and aryl-p-phenylenediamines are new. They act as antiozonants when added to natural and synthetic diene rubbers.

The alkyl groups of the N-fluorenyl-alkyl-p-phenylenediamines include saturated hydrocarbons of 1 to 20 carbon atoms, including, for instance, methyl, ethyl, propyls, butyls, pentyls, octyls, decyls, dodecyls, stearyl, etc. as well as cyclobutyl, cyclohexyl, cyclooctyl, etc. The alkyl derivatives include also nitrogenand oxygen-containing heterocyclic groups as, for example, morpholinyl, piperidinyl, pyrrodinyl, hexamethyleneiminyl, 2,6-dimethylmorpholinyl, etc. They include also the hydroxy and alkoxyl derivatives of alkyl groups of 1 to 20 carbon atoms in which the alkyl of the alkoxy groups contain 1 to 4 carbon atoms. The hydroxy and alkoxy groups may be attached to any carbon of the alkyl group and include, for example, hydroxymethyl, methoxymethyl, 1-hydroxylbutyl, 2-pentoxyoctyl, 9-hydroxydecyl, etc.

The aryl groups of the N-fluorenyl-aryl-p-phenylenediamines include, for example, phenyl, naphthyl, tolyl, propylphenyl, butylphenyl, xylyl, benzyl, phenethyl, biphenyl, alpha and beta ethyl naphthyl, 0-, mand p-methyl biphenyl, fluorenyl, indanyl and other benzenoids and hydroxy and alkoxy derivatives thereof in which the alkoxy groups include 1 to 4 carbon atoms and the hydroxy and alkoxy groups may be attached at any position on the ring or in the side chain as alpha or beta hydroxyethylphenyl, etc. The term benzenoid is used herein to include benzene and fused benzenoid rings which may be joined directly or indirectly and may include side chains.

The rubbers that are stabilized include natural rubber and synthetic diene rubbers including polybutadiene, polyisoprene, butadiene-styrene copolymer, butadiene-isoprene copolymer, etc.

The antiozonants are added in any usual amount, such as, for example, 0.5 to 10 percent of the weight of the rubber and preferably from 1 to 5 percent.

The following examples are illustrative.

EXAMPLE I N-fluorenyl-N-phenyl-paraphenylenediamine The preparation is illustrated by the following equation:

E Q H 3,839,451 Patented Oct. 1, 1974 The following materials were added to a Parr shaker apparatus:

27.6 g. (0.15 mole) p-aminodiphenylamine 27.0 g. (0.15 mole) 9-fluorenone 1.5 ml. glacial acetic acid 0.15 g. PtO (Adams catalyst) 100 ml. absolute ethanol EXAMPLE II N-fluorenyl-N'-isopropyl para-phenylenediamine The preparation is illustrated by the following equation:

rem-@arn-omonm f E CH;

nn -nn-on 31120 cm The following materials were added to a Parr shaker apparatus:

27.0 g. (0.15 mole) N-isopropyl-p-nitro-aniline 27.0 g. (0.15 mole) 9-fluorenone 0.2 .g. PtO (Adams catalyst) 2.5 ml. glacial acetic acid 100 ml. absolute ethanol The vessel was placed under 50 p.s.i. of hydrogen. After 0.6 mole of hydrogen had reacted (3.5 hours) the reac tion was stopped, the catalyst filtered, and the solvent evaporated. The resulting product is N-fluorenyl-N'-isopropyl para-phenylenediamine. Melting point -87 C. The IR and NMR spectra verified the structure of the compound.

The fluorenyl derivatives of this invention can be used as antiozonants in diene rubbers. The following examples are illustrative of their use in oil-extended tire sidewall stocks, but it is to be understood that other fluorenyl derivatives included generally herein may be similarly utilized as antiozonants and any of the fluorenyl derivatives of the invention may be used as antiozonants in other rubber compounds, including tread stocks, hose, motor mounts, conveyor belts, etc.

The antiozonants of this invention may be used alone or in combination with other antiozonants and with antioxidants. The rubber stocks may include other reinforcing agents than carbon blacks as, for example, silica, but it is not necessary that a reinforcing agent be included.

ANTIOZONANT EVALUTIONS OF THE EXPERIMENTAL COMPOUNDS The two antiozonants of Examples I and II were compounded in a general formula and a commercial antiozonant Santoflex 77 (N,N-di-secondary heptyl paraphenylenediamine) was similarly compounded, and the dilfercut stocks were tested against a blank containing no antiozonant. The formula used is set forth in the following table. The formula need not include any reclaim but may include as much as 22.5 percent of reclaim.

A B o D E 5 .5 1.4 2.5 1.4 Santoflex 77 1.4 1.4

The reclaim was a standard grade of reclaim rubber.

The various stocks were cured at 300 F. The physical properties are given for 23-minute cures and the ozone evaluations were made on the same stocks by treatment in an ozone chamber using 60 p.p.h.m. of ozone. (Except for said larger amount of ozone, the test was ASTM test D-1149-64.) Two ozone test were conducted; one for 7 hours at 40 F., and the other for 14 hours at 95 F.

Stress-strain properties 25 A B C D E 300% modulus, p.s.i 775 775 700 725 700 400% modulus, p.s.i 1,050 1,075 1,025 1,100 1,075 Tensile strength 1,475 1,525 1,425 1, 600 1,375 Ultimate elongation, percent--- 530 5 540 560 450 Ozone evaluation 7 hours at F Broke 14 hours at F Broke Moderate. 35 1 Very, very slight.

I Slight.

I claim:

1. N-fluorenyl-N-substituted paraphenylenediamine in which the N'-substituent is selected from the group consisting of phenyl, naphthyl, tolyl, xylyl, and alkyl containing 1 to 20 carbon atoms and alkyl containing 1 to 20 carbon atoms which is substituted by a substituent selected from the group consisting of hydroxy and alkoxy in which the alkoxy group contains 1 to 4 carbon atoms.

2. N-fiuorenyl-N'-pheny1-paraphenylenediamine.

3. N-fluorenyl-N'-isopropyl-paraphenylenediamine.

References Cited UNITED STATES PATENTS 3,507,826 4/1970 Lal et a1 26045.9 2,691,642 10/1954 Faulkner 26045.9 R

LORRAINE A. WEINBERGER, Primary Examiner C. F. WARREN, Assistant Examiner US. Cl. X.R.

260-239 B, 247.5 R, 293.62, 326.85, 570.5 P, 571, 573 

1. N-FLUOROENYL-N''-SUBSTITUTED PARAPHENYLENEDIAMINE IN WHICH THE N''-SUBSTITUENT IS SELECTED FROM THE GROUP CONSISTING OF PHENYL, NAPHTHYL, TOLYL, XYLYL, AND ALKYL CONTAINNING 1 TO 20 CARBON ATOMS AND ALKYL CONTAINING 1 TO 20 CARBON TOMS WHICH IS SUBSTITUTED BY A SUBSTITUENT SELECTED FROM THE GROUP CONSISTING OF HYDROXY AND ALKOXY IN WHICH THE ALKOXY GROUP CONTANS 1 TO 4 CARBON ATOMS. 